Purifying a Shadow Pokémon will improve their appraisal and reduce the amount of Stardust and Candy required for them to Power Up, Evolve, or learn a new attack. When Purified, a Shadow Pokémon will forget Frustration and learn Return, a Charged Attack that's exclusive to Purified Pokémon.

Should I purify my Pokemon?

Many players often reiterate the line that purifying a Pokemon isn't worth it in almost any situation, but there are certainly situations where a purified Pokemon is more useful, even if it loses the 20% damage buff that comes with being a Shadow Pokemon.

Does purifying a Pokemon change its stats?

Purifying a shadow Pokemon will add two points to each IV stat, so if you have a 13/13/13 shadow Pokemon, after purifying it, you'll be left with a 100% IV Pokemon. ... Above the options to power up and evolve the Pokemon, is a Purify button.